CANONAE-1 PROGRAM

Similar models: other A-seriesCanons

Battery: 6V PX28 or 544 (negativeground)

Fig. 1-top cover removed, rewindside

Fig. 2-top cover removed, wind side

Fig. 3-bottom cover removed

Fig. 4-front view, covers removed

Fig. 5-top view, IC4 lifted out FIGURE 1BATTERY-TEST SWITCH KVc

Fig. 6-top view, piezo beeperremoved

Fig. 7-mirror box, bottom view

H

IJKLMN

oP

F

Wind overtravelConnecting-lever armTravel time, second curtainTravel time, first curtainMaximum-aperture pinAuto apertureAuto aperture and readoutBrake, second curtainBrake, first curtain

A-D SIGNAL CAD

Fig. 19-IC3, pin voltages with SW1closed

ADJUSTMENT LOCATIONS:Film-speed contact AAuto exposure, gain BAuto exposure, level COffset 0Oscillator clock frequency EManual 1/1000 FSW5 G

Fig. 11-back of AE control unit -maximum-aperture resistor

Fig. 9-mirror box, top view - LEDdisplay board

Fig. 8-mirror box, rewind side -S.AVE contact

Fig. 10-front view, mirror boxremoved

Fig. 12-top view, counter-mechanism plate removed

Fig. 14-sprocket timing

Fig. 16-IC4, pin voltages with SW1closed

Fig. 13-wiring pictorial, top of flex

Fig. 15-top of flex, fixed-resistoradjustment locations

Fig. 17-IC1, pin voltages with SW1closed

Fig. 18-IC2, pin voltages with SW1closed

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J

Note: Of the electronic adjustments,you normally only have to adjust themanual speeds (F) and the autospeeds (C).

ADJUSTMENT AND TEST VALUES:Curtain-travel time: 10.Sms (34mmdistance), 9.9ms (32mm distance)

Flange-focal distance: 42.14mm(flange to pressure-plate rails),41.9mm (flange to film-guide rails)

Clock freq uency: 30,117 - 34,134 Hz(measured at OSC test point, Fig. 2)

Frequency of oscillator that drivespiezo beeper: 4,096 Hz (measured atpin 10 of IC2 or at yellow wire to piezobeeper)

Battery test: With 4.8V applied to thebattery terminals, the piezo beepershould beep at the fastest speed(6.S Hz). The frequency decreases asyou decrease the applied voltage.With 3.SV applied, the piezo shouldbeep at the slowest speed (1 Hz). Thepiezo s.hould not beep with 3.3Vapplied. 2.SV P-P signal.

Self-timer: 1.0 second delay. Piezoshould beep at 2 Hzfor first 8secondsand 8 Hz for final 2 seconds. SV P-Psignal.

Vc voltage: 1.3V (measured at Vc testpoint, Fig. 2)

KVc voltage: 1.6V (measured atvariable resistor C, Fig. 1)

Wind overtravel: With the shuttercocked, the second-curtain latch(MG3 armature) should engage thenotch in the second-curtain cam withno space gap (minus latch). Check bypulling the second-curtain latch outof engagement with the second-curtain cam. Then allow the second-curtain latch to spring back intoengagement. The second-curtainlatch should again fully engage thenotch in the second-curtain cam. Toadjust, loosen the two setscrews androtate the second-curtain cam.

Wind sequence: Check by slowlyadvancing the wind lever. Near theend of the wind stroke, the first-curtain latch should engage the first-curtain gear (you can hear the "click"as the connecting lever moves aslight distance toward the chargecam, Fig. 3). Next the second-curtainlatch should drop into engagementwith the second-curtain cam. Finallythe transport latch should engage thewind shaft and SWS, Fig. 2, shouldopen.

Connecting-lever arm: Theconnecting-lever arm holds thesecond-curtain latch disengagedfrom the second-curtain cam until theconnecting lever returns followingthe wind stroke. Check by advancingthe wind lever until the charge campushes the connecting lever themaximum distance toward the rewindend of the camera. There should nowbe a space gap of 0.2 - OAmmbetween the edge of the second-curtain cam and the second-curtainlatch. Adjust by bending theconnecting-lever arm.

Switch SWS:SWSopens at the end ofthe cocking cycle as the transportlatch drops into engagement with thewind shaft. As long as SWS remainsclosed, the shutter won't release.Check by slowly advancing the windlever. Stop the moment the second-curtain latch drops into engagementwith the second-curtain cam. At thispoint, SWSshould still be closed andthe shutter should not release whenyou close SW2. As you complete the

RED

FOCUSING-SCREEN PIEZOLATCH BEEPER

wind stroke, SWS should open. Toadjust, slowly advance the wind leveruntil the second-curtain latch justdrops into engagement with thesecond-curtain cam. Then turn theSWS eccentric pin counterclockwiseuntil it touches the SWScontact wire.From this point, turn the eccentric pinslightly further in a counterclockwisedirection - a distance equal to thewidth of the screwdriver slot in theeccentric. Now complete the windstroke. SWS should open, and thereshould be a space gap of at least0.1Smm between the wire contactand the eccentric pin.

ADJUSTMENT SEQUENCE,EXPOSURE:

1. Manual speeds. Adjust at 1/1000with variable resistor F,·Fig. 2. Ifnecessary, you can also bend thecount (trigger) switch SW4 toadjust 1/1000. If SW4 openssooner, you get a faster speed.

2. Auto aperture (normally notnecessary unless you've

SPT JOURNAL/17

a.

b.

3.

replaced the AE pattern board,Fig. 8). Connect a 4.7K resistorbetween ground and the CCCpad on the flex, Fig. 1. The lensshould now program the f/4aperture. To check, release theshutter. Then turn thediaphragm-setting ring off theauto position to f/16. Push in thestop-down slide, Fig. 4, to stopdown the lens; the diaphragmshould close to f/4. Verify byslowly turning the diaphragm-setting ring toward the largerapertures; note when thediaphragm leaves start to open.When the leaves start to open,the diaphragm-setting ringshould be at the f/4 setting.Adjust by bridging lands on theLED board, Fig. 9, or by breakingconnections on the AE patternboard, Fig. 8. Procedures:Underexposure. To increase thesize of the aperture 1/8 stop,bridge the A1 land to the landdirectly above it, Fig. 9 (you canreach the lands from the front ofthe camera without lifting asidethe SV base plate). To increasethe aperture 1/4 stop, bridgeboth the A1 land and the A2 landto their adjacent lands. Thisadj ustment affects both the LEDreadout and the actualdiaphragm opening.Overexposure. To decrease thesize of the aperture 1/8 stop,bridge the A2 land to the landdirectly above it, Fig. 9. For alarger reduction in the aperturesize, cut the lands of the AEpattern board as shown in Fig. 8.Cutting at "a" reduces theaperture size 1/8 stop. Cutting at"b" reduces the aperture size 1/4stop. Cutting at "c" reduces theaperture size 3/8 stop. Cutting at"d" reduces the aperture size 1/2stop. Cutting the patterns on theAE pattern board changes thediaphragm opening withoutaffecting the LED readout.Auto exposure. Check at ASA100, light levels EV 9 through EV15, K-factor 12.50. At eitherprogram or auto f/stop, theexposure error should not varyby more than 1 EV. Adjust for 0EV error with variable resistor C,Fig. 1. For a larger exposurevariation, you can replace thefixed gain resistor (8 in Fig. 1).Install a 10K variable resistor inplace of the gain resistor. Adjust

the 10K resistor until you havethe same amount of EV error atEV 9 and EV 15. Then adjust thelevel resistor to correct the errorat EV 12. Remove the variable10K resistor, measure itsresistance, and replace with afixed resistor of the same value.

ADJUSTMENTS NOT NORMALLYREQUIRED:

1. Clock frequency. Check if youreplace IC1 or if you can't bringin the shutter speeds. Measurewith a scope or frequencycounter at the OSC test point,Fig. 2. Adjust by changingresistor R2 (E in Fig. 1) for a

IC2 PIN 4 IC2 PIN 5TEST POINT TEST POINT

frequency of 30,117 - 34, 134 Hz(a smaller resistance valueincreases the frequency). Youcan find the proper resistance byinstalling a 200K variable resistorin place of the fixed resistor;adjust for the proper frequencyand then install a fixed resistor ofthe same value. Alternatemethods of measuring thefrequency:

a. Measure the shutter speed at1/2 second. If the shutter speed is476 to 525ms, the frequency iscorrect.

b. Time the self-timer delay.Adjust the frequency for a delayof 10 seconds.

2. Offset. Check if you replace IC4.

18/SPT JOURNAL

Unsolder one end of resistor R5,Fig. 15. Short pin 11 of IC4 to pin9 (output shorted to input). Nowmeasure the voltage between pin10 of IC4 and ground. Alsomeasure the voltage from pin 11of IC4 to ground. The secondreading should be the same as(or not more than 5mv less than)the first reading. To adjust,remove the offset resistors (R3and R4 positions, Fig. 15- theremay be only one offset resistorinstalled, or both positions maybe open). Install a 200K variableresistor in the R4position. Adjustuntil the voltage at pin 11 equalsor is no more than 5mv less thanthe voltage at pin 10. Then installa fixed resistor of the same value.If you can't bring in the offsetadjustment with the variableresistor at the R4 position, usethe R3 position.

3. Maximum-aperture pin. Check ifyou replace the maximum-.aperture resistor, Fig. 11. Youcan make the adjustment withthe mirror box removed orinstalled. Procedure:

a. The white wire and the black wireto the maximum-apertureresistor, Fig. 13, connect acrossfixed resistor R108. First find thevalue of R108 - disconnect thewhite and black wires andmeasure the resistance betweenthem. Standard value - 1.5K.

b. If R108 measures 1.5K, installthe 111.4 lens. Alternately, use adepth gage set to 8.10mm todepress the maximum-aperturepin. Now measure the resistancebetween the white wire andground. You should measure9.32K..

c. If R108 measures some valueother than 1.5K, calculate acorrection factor. Divide theactual resistance by 1.5K.Multiply 9.32K by the correctionfactor to find the value of themaximum-aperture resistor withthe f/1.4 lens installed.

d. Also check the resistancebetween the white wire andground with the maximum-aperture pin depressed 5.7mm;you should measure 4.16K (timesthe correction factor). With themaximum-aperture pin de-pressed 8.38mm, you shouldmeasure 11.03K (times thecorrection factor).

FIGURE 7

e. Adjust so all three readings arewithin 5%of the specifications byturning the setscrew inside themaximum-aperture pin (loosenthe ce'ment with M.E.K.). Turningthe setscrew clockwise increasesthe resistance.

4. Film-speed contact. Check ifyou replace the film-speedcontact, base plate, or top cover.Adjust the eccentric (A in Fig. 1)so the film-speed contacttouches only the correct land. Tocheck, temporarily connectwires to the SV test point, Fig. 1,and to ground (you can use oneof the ground tabs on IC1 for oneof the wires). Install the top coverand connect a DVOM betweenthe two wires. The DVOM shouldread between 2.5K and 4.5K (if itreads lower than 1K, reverse theohmmeter leads).

a. Rotate the film-speed contactuntil the brush near the eccentricpin is on the ASA 3200 land of thefilm-speed base plate (the lastland, placing the eccentric pin atthe. back of the camera). Recordthe resistance reading.

b. Rotate the film-speed contactclockwise until the brush is onthe ASA 12 land (the first land, .placing the eccentric pin to thefront of the camera). Record theresistance reading.

. c. Temporarily replace the topcover and the film-speed dial. SetASA 3200. The resistancereading should match that in "a."Set ASA 12. The resistancereading should match that in "b."

d. Lock the film-speed dial at ASA100 and note the resistancereading. Without disengagingthe lock, rotate the film-speeddial as far as it will go in both aclockwise and a counterclock-wise direction to take up the play.The resistance reading shouldnot change. Also assure that youcan't change the resistancereading at the ASA 3200 positionby taking up the play in the film-speed dial.

BASIC USER'S OPERATION:

1. At the program setting and withthe lens at auto, the cameraautomatically sets the dia-phragm opening and the shutterspeed (2 seconds - 1/1000). The"P" (program) LED at the top ofthe viewfinder display turns on

SPT JOURNAL/19

when you depress the releasebutton part way. When thecamera must program a shutterspeed of 1/30 or slower, the "P"LED blinks. The "16" LED blinksto indicate overexposure, andthe LED indicating the maximumaperture of the lens blinks toindicate underexposure.

2. At the manual shutter-speedsettings with the lens at auto, thecamera automatically sets thediaphragm opening. The LEDdisplay shows the aperturewhich will be automatically set. Ifthe LED blinks, the camera can'tprogram a proper aperture forthe shutter-speed setting andlight conditions.

3. At the manual f/stop settings,the "M" LED turns on at the top ofthe display.

4. The dedicated flash auto-matically sets the shutter speedto 1/60, regardless of the speed-knob settings (except "B"). Whenthe flash charges, the flash LEDat the bottom of the display turnson.·The f/stop LEDs show thef/stop which the dedicated flashwill program. After the flashexposure, the flash LED blinksfor two seconds if the shootingdistance provided properexposure with the 188A flash (aslong as you keep the releasebutton partially depressed).

5. Pushing the battery-test buttoncauses the piezo beeper to beepat a frequency according to theactual battery voltage; thefrequency decreases as thebattery voltage decreases. Thebattery-test button also serves asa cancel button for the self-timer.Set the self-timer with the switchunder the wind lever.

6. The preview button on the frontstandard closes SW1' (the sameas pushing the release buttonpart way to close SW1). The AElock button (above the previewbutton) locks in the exposureinformation. As long as you keepthe release button partiallydepressed, the exposureinformation remains in memory;it's not necessary to hold in theAE lock button.

DISASSEMBLY HIGHLIGHTS:

Locations of left-hand threads:screws holding pinions on tops ofwinding rollers, Fig. 12

20/SPTJOURNAL

Settings for disassembly: ASA 100,Program (for reference)Precautions:1. Be careful to avoid turning the

film-speed brush after youremove the film-speed dial atASA 100. Once you remove thetop cover, note the position of thefilm-speed brush, Fig. 1. You canthen set ASA 100for adjustmentswith the top cover removed.

2. Remove the battery beforeunsoldering wires.

Sequence:1. bottom cover (3 screws in

chrome models, 2 screws inblack models)

2. front cover (4 screws)

YELLOW

WHITE

BLUE

GREEN

BLUE

FIGURE 9

3. top cover (cable-release pininside release button will beloose) --rewind knob and film-speed

dial (snap ring)-cemented insert above wind

lever-release-button decorator plate

(2 screws)-wind lever (unscrew retainer-

2 loose washers). -on/off/self-timer lever (snap

ring)-top-cover screws

4." unsolder black wire from P.C.terminal

5. unsolder white and green top-cover wires from flex

SW9

sw,

Reassembly highlights:

1. After resoldering the top-coverwires, slip the black X-sync wireunder the piezo beeper, Fig. 4.Route tile green and white wiresso they don't interfere with thefilm-speed contact or thebattery-test switch.

2. Set the speed selector to theprogram position (slot pointingto front of camera) beforeseating the top cover, Fig. 2.

Sequence to remove mirror box:1. right and left front leatherette2. remove cover plate, rewind side

of body (3 screws) - spacers forback latch loose

3. unfold section of flex coveringMGl wires, Fig. 4

4. unsolder black and red MGlwires from flex

5. unsolder wires from top of flex-violet to SW1'-white and black to maximum-

aperture resistor-orange to S.AVE (diaphragm)

contact-blue, green, violet, and red to

LED display board-yellow to piezo beeper-gray to battery-test switch

6. remove film-speed brush (snapring)

7. remove battery-test ground platewith switch (2 screws)

8. remove screw holding film-speed base plate, Fig. 1

9. lift up film-speed base plate toreach piezo beeper

10. remove piezo beeper (3 screws- long screw goes to front ofcamera)

11. remove 2 upper mirror-boxscrews, back of camera

12. remove 5 front-plate screws13. remove front-plate/mirror-box

assembly

Note: It's possible to remove thefront-plate/mirror-box assemblywithout taking out the piezobeeper. However, it's mucheasier to remove and replace theassembly with the beeperremoved. Also, removing thebeeper prevents chance ofdamage to the LED displayboard, Fig. 9.

Reassembly highlights:

1. Replace the front-plate/mirror-box assembly with the shutterand mirror released, mirrordown. The MG2 armature mustalso be in the released position(away from the magnet).

2. Route the wires to the back ofthe flex, Fig. 1, as you install thefront-plate/mirror-box assembly.

3. After installing the front-plate/-mirror-box assembly, test bycocking the shutter; make sureyou can't continue to advancethe wind lever after the cockingstroke. Release the mirror bypushing the MG2 armature awayfrom the magnet, Fig. 3. Theshutter should release and themirror should return to the downposition.

4. Install the two locating

FIGURE 10

(shoulder) front-plate screwsfi rst.

5. Route the section of flex thatextends to the bottom of thecamera between the piezobeeper and the film-speed baseplate, Fig. 4.

Sequence to remove flex circuit(mirror box does not have to beremoved):

1. unsolder all wires from flex,Fig. 13, Fig. 3, and Fig. 4

2. unsolder red battery wire fromon/off switch

3. remove film-speed brush (snapring)

4. remove batter-test ground platewith switch (2 screws)

5. remove insulator tape, bottom offlex, Fig. 3

6. remove ground screw andwasher, bottom of flex, Fig. 3

7. unsolder bottom section of flexfrom MG2 (2 connections) andfrom power-winder terminalblock (4 connections)

8. remove brass clip at top ofeyelens

9. Ifit IC4 from the SPD fresnel-lens frame

10. shutter-speed board

Note: If you're replacing the flex,remove the three screws holdingthe shutter-speed board to thecounter-mechanism assembly.However, if you're removing theflex to reach the shutter, you cantake out the shutter-speed boardand the counter-mechanismplate together. Remove the twoscrews holding the counter-

mechanism plate to the camerabody.

11. lift off the on/off/self-timerbrush (hold aside detent)

12. remove 3 screws holding on/off!self-timer switch board

13. unsolder flex from SWl andSW2 (2 connections)

Note: If you're removing thecounter-mechanism plate withthe flex, you don't haye tounsolder the SW1/SW2 con-nections.

14. unsolder SW5 from flex andremove the SW5 contact wire,Fig. 2

15. unsolder SW4 from front of flex,Fig. 4

16. remove flex-circuit assembly

5PT JOURNAL/21

Reassembly highlights:

1. If you removed the counter-mechanism plate with the flex,the counter-advance gear, Fig.12, will be loose. Push the first-curtain brake lever against itsspring pressure to lift out thecounter-advance gear. Avoidgrasping the upper notched endof the counter-advance gear withyour tweezers. If you scratch thisend, the counter dial mayadvance two positions during thecocking cycle. On reassembly,seat the counter-advance gear inits bearing hole as shown. Thenpush the first-curtain brake leverback into position.

2. When you replace the sectionof flex above the eyelens, slip IC4behind the tab on the SPDfresnel-lens frame. Make sure theends of IC4 fit between the twopositioning lugs.

Sequence to remove shutter:

FIGURE 12

PURPLE

WHITELED DISPLAY BOARD

TOP-COVER CCC CONTACT

4.

5.

7.

BATTERY· TESTSWITCH

GRAY

2. Before replacing the windingunit, turn the clutch cam (centerof one-way clutch) clockwise tothe position shown in Fig. 12.

3. Before replacing the chargegear, rotate the sprocket to thetimed position, Fig. 14.

4. Seat the charge gear so that oneof the three gaps betweencharge-cam lobes faces thecenter of the camera, Fig. 3. Pullaside the spring-loaded levers bythe rewind button to allow thecharge gear to seat fully.

PIEZOBEEPER

BLUE

GREEN

PURPLE

ORANGERED

MAXIMUM-

APERTURE {RESISTOR

SW1'

LED DISPLAY {

BOARD

S.AVELED DISPLAYBOARD

TOP-COVERAV EF CONTACT

FIGURE 13

Reassembly highlights:

1. As you replace the wind shaft,make sure one of its three lugspasses into the gap in the idlergear, Fig. 12.

bottom)11. shutter assembly

Note: The black X-sync wire iscemented above the shutter. Cutloose the cement from the bodyas you remove the shutterassembly. Use the battery box asa "handle" to lift out and replacethe shutter.

6.

1.2.3.

mirror boxtripod socket (3 screws)disconnect and remove springfrom rewind end of connectinglever, Fig. 3connecting lever (snap ring atone end, E-clip at other end) -bushing on underside ofconnecting lever will be looseremove screw holding chargecam and charge gear, Fig. 3(screw is cemented - use M.E.K.or acetone to soften cement)remove charge cam and chargegearflex circuit

Note: It's not necessary todisconnect the bottom section ofthe flex. Just follow the flex-removal sequence to lift aside thetop section. Remove the counter-mechanism plate together withthe flex. Also remove the piezobeeper (if you did not remove thebeeper to pull the mirror box).

8. winding unit at top of camera(3 screws)

Note: Lift the winding unitstraight up to avoid dislodgingthe springs and rollers of theone-way clutch, Fig. 12.

9. wind shaft (push up frombottom of camera)

10. remove 4 shutter-assemblyscrews (2 at wind side, 1 atrewind side, locating screw at

22/SPT JOURNAL

1.5V-

6. IC1 metering output. Check theoutput signal at pin 5. Scopesettings: .5v/cm, 2ms sweep. Thetrace should change as youchange the light level. No change- troubleshoot IC4 and IC1.

shown when you close thebattery-test switch; the traceshould pulse on and off at afrequency depending on theapplied voltage. No trace -troubleshoot IC2.

7. IC2 metering output. Check theoutput signal at pin 4 of IC2.Scope settings: 5ms sweep, .5v/cm. The trace should changeas you change the light level. Nosignal - troubleshoot IC2. Nochange in signal - troubleshootIC4, IC1, IC2. The trace shouldalso change when you connect a4.7K resistor between the CCCcontact (white-wire connection)and ground. No change - IC2.

5. SV signal. Check at the SV(film-speed) test point, Fig. 1, orat pin 7 of IC1. Scope settings:2ms, .1 v/cm. The drawing showsthe approximate trace at ASA 100with SW1 closed. Changing thefilm-speed setting shouldchange the trace. No change -check film-speed contact.

i2.SV

t

LOW LIGHTHIGH LIGHT

T3 eM

-11-.6 eM

ov

2. A-D signal. Check the analog-to-digital conversion at pin 1 of IC2or at the lead of the CADcapacitor that connects to pin 1,Fig. 2. Scope settings: .05 v/cm,2ms sweep time. When you closeSW1, you should get the A-Dtrace. The slope of one side of thetrace should change as youchange the light level on IC4, Fig.5. No change in trace - trouble-shoot IC4, IC1, and IC2.

OSC test point and ground, Fig.2. Scope settings: 10 micro-seconds sweep time, .50r 1v/cm.The square wave should riseabove the OVline asshown (if thesquare wave rides a positivevoltage rather than OV, discon-nect the blue wire that goes to theLED display board, Fig. 13 - ifthe trace then appears normal,IC3 is defective). No clock trace- troubleshoot IC1.

3. Output bus. Check between pin20 of IC2 and ground. Scopesettings: 50 microseconds sweeptime, .5 v/cm. When you closeSW1, you should get the traceshown. The output signalappearing between these twopips should vary as you changethe light level or film-speedsetting. No output signal -troubleshoot IC2. No change inoutput signal - troubleshootIC4, IC1, and IC2.

SWITCH FUNCTIONS:

SWO.Battery (on/off) switch. TurningSWO to the "on" position connectsthe positive side of the battery to theemitter of TR1, Fig. 2.

Note: Switch numbering corresponds to other A-series Canons.

SW1, SW1'. Metering switch. Closingeither SW1 (by pushing the releasebutton part way) or SW1' (by pushingthe button on the front standard)turns on TR1 to supply the E1voltageto the circuit. The E1voltage appearsat the magnets and at the IC's onlywith TR1 turned on.

SW2. Release switch (under SW1).Closing SW2 connects pin 17 of IC2to ground to release the shutter.

SW4. Count switch, Fig. 4. Closedwith the shutter cocked, open whenthe first curtain starts to run. WhenSW4 opens, the circuit startscounting clock pulses to determinethe shutter speed.

SW5. Power-winder switch, Fig. 2.With the shutter cocked, SW5 closesand connects power-winder pin #2,Fig. 3, to ground. SW5 also connectspin 19 of IC2 to ground to prevent theshutter from releasing. With theshutter fully cocked, SW5 opens anddisconnects the power-winder pinand pin 19 of IC2 from ground.

SW7. Self-timer switch. Setting theself-timer position connects pin 16 ofIC2 to ground.

SW8. Battery-test switch. ClosingSW8 connects pin 6 of IC2 to groundto turn on the piezo-drive oscillator.

SW9. Memory switch, Fig. 8. ClosingSW9 connects pin 4 of IC3 to groundto hold the exposure data in memory.

SW11. Auto/manual switch, Fig. 7.Setting the lens to a manual f/stopconnects pin 3 of IC3 to ground.

SW12. TV switch controlled by theshutter-speed brush. Setting theshutter speed connects the properpins of IC2 (12,13, 14, or 15) toground to program the shutter speed.

OSCILLOSCOPE TESTS:

1. Oscillator (clock). Set autosweep and adjust the verticalposition so that the trace is on thecenter (OV) line. Close SW1 andcheck the oscillator between the

4. Oscillator that drives piezobeeper. Check at pin 10 of IC2 orat the yellow-wire land (theyellow wire going to the piezobeeper). Scope settings: 50microseconds sweep time, .5v/cm. You should get the trace

SPT JOURNAL/23

8. S.AVE (segmented aperture-value electrode). Check at pin 22of IC2, shutter cocked and SW1closed. Scope settings: .1mssweep, .5 v/cm. Each time theS.AVE brush touches a contact

as the diaphragm closes, it shortsthe pin 22 signal to ground.

9. Timing signal. Check at pin 5of IC2. Scope settings: .5 v/cm,5ms sweep. No signal - replaceIC2.

push in the maximum-aperturepin, Fig. 4, you should measurearound 1.5V. No change - checkthe maximum-aperture resistorby measuring the resistancebetween the white wire, Fig. 13,and ground. The resistanceshould go from 4K to around 11 Kas you push in the maximum-aperture pin. If the maximum-aperture resistor checksproperly, but you don't get thevoltage change at pin 2, replaceIC4.

2. IC1. Analog and digital IC thatdrives the magnets, provides theoscillator clock signal, providesthe KVc adjustment voltage, andsupplies the metering signal tothe CPU IC2. To check:

LINE PERPENDICULARTO CAMERA BACK

FIGURE 14

Rl0

DVR2

IC3:!-- COLLECTOR

1~C2RS Rllo R9

f. Check the output metering

signal at pin 5 ("OscilloscopeTests," #5). No change in signal- replace IC1.

3. IC2. CPU digital IC that suppliesthe timing and mode signals toIC1 and the readout signal to IC3.Also provides the oscillator thatdrives the piezo beeper. Tocheck:

a. Check for E1 at pin 3. No voltage-check the solder at pin 3 andground pin 11 and the continuitybetween pin 3 and the collectorof TR1.

b. Check for Vc voltage at pin 9.No voltage - troubleshoot IC4and check for continuitybetween pin 9 of IC2 and pin 7 ofIC4.

Rlo

'BVR1D

FIGURE 15

a. Check for E1 at pin 17. Novoltage - check solder at pi n 17and continuity between pin 17and the collector of TR 1.

b. Check for Vc at pin 11. Novoltage - troubleshoot IC4 andcheck for continuity between pin11 and pin 7 of IC4.

c. Check for KVc voltage at pin 9;you should measure around1.6V. No voltage or incorrectvoltage - replace IC1.

d. Check the oscillator clock signalat pin 13 ("Oscilloscope Tests,"#1). No signal - replace IC1.

e. Check the metering input at pin6. The voltage should change asyou change the light level. Nochange - troubleshoot IC4.

Note: Transistor TR1, Fig. 15, turnson when you close SW1 to supply theE1 voltage (around 6V) to all four ICs.Before troubleshooting the ICs,check for the E1 voltage at the TR1collector with SW1 closed. No E1

voltage - proceed to "Trouble-shooting" section.

IC FUNCTIONS AND TESTPROCEDURES:

24/SPT JOURNAL

1. IC4. Analog amplifier for SPD,Fig. 5. Also supplies the Vcconstant voltage. To check:

a. Check for E1 at pin 6. No voltage-check solder at pin 6 andground pin 1. Also checkcontinuity between pin 6 andcollector of TR1.

b. Check for Vc voltage at pin 7;you should measure approxi-mately 1.3V with SW1 closed. Novoltage or incorrect voltage -replace IC4.

c. Check the output of the SPDamplifier at pin 11. The voltageshould go more positive as youchange the light striking theSPD. No change - replace IC4.

d. Check the AR5 output at pin 4.The voltage should go morepositive as you decrease the lightstriking the SPD. No change -replace IC4.

e. Check the maximum-aperturecorrection signal at pin 2. Youshould measure 1.8V without alens on the camera. When you

c. Check for the oscillator clock

signal at pin 8. No signal -troubleshoot IC1 and check for

continuity between pin 8 of IC2and pin 13 of IC1.

d. Check the A-D signal at pin 1("Oscilloscope Tests," #2). Nochange in signal with light-levelchanges - check the output ofIC1 at pin 5 ("Oscilloscope Tests,#6). If the voltage signal at pin 5of IC1 does change with light-level changes, but the A-Dvoltage doesn't change, replaceIC2.

e. Check the output bus signal atpin 20 ("Oscilloscope Tests," #3).No signal - replace IC2.

GND1 13O.W

1.8V (F/S.6) --2 - MAX-APERTURE OUT12O.1V

1.2V (1/1.2)1.3V3

~

11ARS OUT - 1.2 - 1.4V1.3 - 1.SV

4 - BV OUT-.,~~

O.7SV1.3V5 SPDO.7SV

E16

81.3V

1.3V7'-Vc SOURCE

FIGURE 16 IC4 (SW1 CLOSED)

FRONT OF CAMERA

t20 - GND

Note: The following symptomsalso indicate a defective IC2 -

(1) The f/stop indication doesnot change to f/4 when youconnect a 4.7K resistor between

the CCC contact (white-wireland, Fig. 1) and ground.(2) The shutter releases whenyou close SW1 or the battery-testswitch.

(3) The battery-test signal is acontinuous tone rather than a

beep.(4) The camera delivers autowith the lens set to a manual

f/stop.

6V

1.3V

5.4V

1V

1-MG3

2

3

4-VEF INPUT

5-METERING OUTPUT

6-METERING INPUT

7- SV INPUT

8-MAX-APERTURE INPUT

MG2-19

MG1-18

17

16

15

14

OSC OUT-13

12

6V

6V

E1

2.3V

0.65V

6V

0.7V

0.6V

4.

a.

b.

c.

IC3. Decoder/driver for LED

display, Fig. 6. Sinc'e IC3 is on theLED display board, it's difficult toreach for troubleshooting.However, you can check inputsignals at the IC3 connectingwires to the top of the flex, Fig.13. Also, you can check pin

voltages by lifting aside the film-speed base plate and removingthe piezo beeper, Fig. 6. Jumperthe ground land on the film-speed base plate to the camerabody. To check:Check for the E1 voltage at thered wire, Fig. 13, or to pin 9. Novoltage - check the red-wiresolder connections and

continuity to the collector ofTR1.

Check for the clock signal at theblue wire, Fig. 13, or to pin 6. Ifthe clock signal rides on apositive voltage rather than onOV, IC3 is probably bad.Check for the input signal at thepurple wire or at pin 7. The signalshould be the same as at pin 20 of

1.6V 9-KVc SOURCE

10 - GND

FIGURE 17 IC1 (SW1 CLOSED)

IC2. If you get the input signal,but the LED display doesn'toperate, IC3 is probably bad.

TROUBLESHOOTING:

Behavior without battery: shutterwon't release

Behavior without lens: only "M"(manual) LED in finder, f/stop indi-cation won't go larger than f/5.6

Typical current draw (6V supplied):35ma with shutter open

Troubleshooting steps for specificproblems:

1. Shutter won't release, no LEDs

Vc-11 1.3VINPUT

Battery voltage to flex

Check for battery voltage (6V) atthe red wire to the on/off switch.

No voltage - battery box orwiring.

Ground screw loose

Check the ground screw at thebottom of the flex, Fig. 3, and theground screw holding the plateunder the battery-test switch,Fig. 1.

On/off switch, poor contact

Check for battery voltage at theemitter of TR1, Fig. 15, withoutclosing SW1. No voltage - poorcontact of on/off switch or breakin flex between TR1 emitter andon/off switch.

SPT JOURNAL/25

FRONT OF CAMERA

IC2, solder connectionsCheck the solder connections at

pins 19, 18, and 17.

SW2, poor contact or solder

Close SW1 and short pin 17 ofIC2 to ground. The shuttershould release and time out. If so,

IC1 and IC2 are good. Theproblem is SW2 or the continuitybetween pin 17 of IC2 and SW2.

IC1 or IC2

Check the MG2 coil between the

red and black wires, Fig. 4.Approximate coil resistance (onelead disconnected) - 330 ohms.

SW5, not opening or shorted toground

Check the adjustment on SW5("Adjustment and Test Values").Also check to make sure the redinsulator is on the switch-

operating pin, Fig. 2. If not, thewire contact will short to ground.

Count (trigger) switch SW4, poorcontact

SW4 should be closed with the

shutter cocked. Try shorting thewire contact of SW4 to ground; ifyou can then release the shutter,the problem is poor contact inSW4.

GND 11

S.AVE 22

CAD - 21OUTPUT - 20

0.24VBUS

SW5 -19

2.3V (SHUTTER COCKED)

OV (SHUTTER RELEASED)

SW4 -18

6V (SHUTTER RELEASED)OV (SHUTTER COCKED)

SW2 -17

2.3V (OV WITHSW2 CLOSED)

SW 7 -16

3.20

15

1.6V OR OV"

14

1.6V OR OV"TV INPUT 13

1.6V OR OV"

12

1.6V OR OV"

"DEPENDING ON POSITION OF SHUTTER-SPEEDCONTACT

4. Viewfinder LEO indication does

not change with change in lightlevel or film-speed setting

Film-speed contact

Check the film-speed signal atthe SV test point, Fig. 1("Oscilloscope Tests," #5). Youshould get a change in the signalas you change the film-speedsetting. No change - check thecontact of the film-speed brush.

Check the voltage at pin 7 of IC2.The voltage should drop to OVwhen you close SW2. If it does,the problem is probably IC1; if itdoesn't, the problem is probablyIC2. Check IC1 and IC2 ("ICFunctions and Test Pro-

cedures").

3. No LEOs in finder, shutteroperates

IC2 or IC3

Check for the output bus signalat pin 20 of IC2 ("OscilloscopeTests," #3). If you don't have ascope, check the voltage at pi n20; a voltage of around 0.24Vindicates the presence of theoutput signal. No output signal- troubleshoot IC2. Outputsignal present - troubleshootIC3.

t

5 TIMING SIGNAL OUT

9 - Vc IN

8 - OSC IN

6 - SW8

4 MODE SIGNAL OUT

2 - ccc

10 - PIEZO-DRIVE OUT

1-A-D

6V

2.3V

ov

E1

1.3V

0.7V

5.3V

1.3V

0.65V

FIGURE 18 IC2 (SW1 CLOSED)

No voltage to base of TR1

Check for approximately 6V atthe base of TR1, Fig. 15. Novoltage - break in flex betweenTR1 base and R9/R10 junction orpoor solder.

TR1 open or poor SW1 contact

Measure the voltage betweenground and the collector of TR1,Fig. 15. You should measure theE1 voltage (close to 6V) whenyou close SW1. No voltage -TR1 open or poor solder to SW1.You can also check TR1 byshorting between the emitter andcollector leads. If the transistor is

the problem, the viewfinder LEOswill turn on.

Oscillator

Check for the clock signal at theOSC test point, Fig. 2 (see"Oscilloscope Tests," #1). If youdon't have a scope, measure thevoltage - a voltage of around0.7V at the OSC test pointindicates that the oscillator is

working. No signal - trouble-shoot IC1 ("IC Fun,ctions andTest Procedures").

IC2 defective

Troubleshoot IC2 ("IC Functionsand Test Procedures").

2. Shutter will not release, LEOswork

MG2, oil contamination or opencoil

To check, close SW1 and short

between ground and the MG2lead that goes to pin 19 of IC1,Fig. 3. The shutter shouldrelease. If not, check MG2 for an

open coil or dirty magnetinterface. Approximate coilresistance - 90 ohms.

No continuity between MG2 andIC1

Check by closing SW1 andshorting pin 19 of IC1 to ground.The shutter should release. If

not, check for poor solder at pin19 or an open between pin 19andMG2.

MG3, open coil

Check the MG3 coil between the

red and black leads, Fig. 3.Approximate coil resistance (onelead disconnected) - 200 ohms.

MG1, open coil

26/SPT JOURNAL

Check the voltage at pin 2. Thevoltage should go from around1.8V to around 1.4V as you pushin the maximum-aperture pin. Ifthe voltage remains at 1.8V,replace IC4.

10. Diaphragm always stops downfully or always sets largestaperture

S.AVE contact or IC2

Check the signal at pin 22 of IC2("Oscilloscope Tests," #8). Cockthe shutter and push in the stop-down slide, Fig. 4. You can nowmove down the diaphragm-control lever. Each time theS.AVE brush touches a contact, itgrounds out the signal at pin 22.

If the signal appears constantly- regardless of the position ofthe S.AVE brush - check for

poor brush contact, Fig. 8, or forpoor solder at the orange wire,Fig. 13. If you never get the signalat pin 22, replace IC2.Alternately, check the resistancebetween the orange wire andground as you move down thediaphragm-control lever. Eachtime the S.AVE brush touches a

contact, you should get directcontinuity (no resistance).

11. Incorrect shutter speeds, or onlyfastest speed and largestaperture

SW1 or SW1', shorted or leakcurrent through insulators

2V

2V

2

YELLOW WIRE

3-SW11

WHITE WIRE

2V4 - SW9

BLUE WIRE

2V5 - SW10

BLUE WIRE

0.7V6 - OSC INPUT

PURPLE WIRE

0.24V7 -INPUT

GREEN WIRE

S.4V8

LED DISPLAYOV OR O.SV

GND

16

17

11

12

18

15

10

13

14

FRONT OF CAMERA

t

E1RED WIRE

FIGURE 19 IC3 (SW1 CLOSED)

Piezo does not beep when youclose battery-test switch

Battery-test switch

Short pin 6 of IC2 to ground. Thepiezo beeper should beep. If itdoes, check the battery-testswitch and the continuitybetween the gray wire and pin 6of IC2.

IC2

Close the battery-test switch andcheck for the oscillator output atpin 10 ("Oscilloscope Tests," #4).No signal - replace IC2. If youdo get the signal, the problem is adefective piezo beeper or theyellow-wire solder connections.

Viewfinder LEOs won't displayan aperture larger than fl5.6,regardless of the maximumaperture of the lens installed

Maximum-aperture resistor,open or poor contact

Disconnect the white wire of the

maximum-aperture resistor fromthe flex, Fig. 13. Measure theresistance between the white

wire and ground as you push inthe maximum-aperture pin. Theresistance should go fromaround 4K to around 11K.

IC4

8.

9.

Alternately, check the resistancebetween the SV test point andground. The resistance shouldvary between 2.5K and 4.5K asyou turn the film-speed brush.

IC4

Check for a changing voltage atthe lead of resistor R7 (the leadcloser to the back of the camera

that connects to IC4 pin 4, Fig.15). The voltage should go morepositive as you decrease the lightlevel. No change - troubleshootIC4 ("IC Functions and TestProcedures").

IC1

Check for the KVc voltage at pin9 (around 1.6V) and the 1.3V Vcvoltage at pin 11. If you get the Vcvoltage but not the KVc voltage,replace IC1. If you get bothvoltages, check the output at pin5 ("Oscilloscope Tests,-" #6). Nochange in output signal -replace IC1.

IC2

Check the A-D signal ("Oscillo-scope Tests," #2)'. If you don't geta change in signal with a changein light level, but you do get thechange at pin 5 of IC1, replaceIC2.

Note: If you aren't certainwhether IC1 or IC2 is at fault, tryconnecting a 4.7K resistorbetwen the CCC contact (white-wire land, Fig. 1) and ground.The display should change to fl4,and the flash LED should turn on.

If the display does not change tofl4, IC2 is the problem. If thedisplay does change, IC1 isprobably the problem.

5. Auto diaphragm opening toosmall or erratic

Oil contamination, MG1

Remove the mirror box to cleanthe MG1 interface.

S.AVE contact (diaphragmcontact), dirty or out ofadjustment

6'. 1/1000 too slow or erratic

Oil contamination, MG3

1/1000 variable-resistor adjust-ment

Count switch SW4, adjust-ment

7. Viewfinder LEOs always onTR1, shorted

SPT JOURNAL/27

TV (shutter-speed) contact, dirtyor poor contact

12. No self-timer

Self-timer switch, poor contact

IC2 or poor solder to pin 16

13. Shutter always delivers 2-secondexposure

Film-speed brush, poor contact

14. Shutter always delivers bulbaction

Count switch SW4, alwaysclosed or shorted to ground

OTHER COMMENTS:

1. You can replace the flex as acomplete unit (electric parts unitCG1-0124-000) or you canreplace individual components(by component number).

2. Operation with an off-brandflash unit having a high-voltagetrigger could damage IC2.

3. You can drop out the focusingscreen inside the mirror box forcleaning. Disengage the latch atthe top of the m1rror box, Fig. 4.